The apparatus and method disclosed herein, in general, relates to a latent print development apparatus. More particularly, the apparatus and method disclosed herein relates to using a pellet comprising a substrate impregnated with a sublimation compound in a latent print development apparatus. The substrate comprises stainless steel wool, fibrous and porous materials, cotton gauze, flax, etc. The sublimation compound comprises compounds such cyanoacrylate, etc.
Cyanoacrylate is used in forensic science for capturing latent prints, for example, fingerprints on non-porous surfaces. When cyanoacrylate is heated beyond its sublimation temperature, cyanoacrylate sublimates into a white vapor that adheres to the residues of a latent print to reveal the print's topography, outline, ridges, etc.
Former devices and techniques for developing latent finger prints produced fairly good results. However, these devices used techniques that were time consuming, taking several hours, and had to be performed in enclosed spaces. In the late 1990s, a different approach was introduced that allows the devices to be used both indoors and outdoors. This approach also significantly reduced the print development time. However, this approach also has a few drawbacks, such as high operational cost, low ease of use, and the requirement to maintain a constant supply of liquid cyanoacrylate.
Another device for developing latent fingerprints uses a brass-housing for holding a porous substrate impregnated with cyanoacrylate. The brass-housing is a replaceable cartridge with a one-time use and is relatively expensive. The brass housing is attached to the exhaust port of a handheld butane torch by a friction fit. When the cyanoacrylate gets depleted during the fuming process, the brass housing has to be removed with pliers or tweezers, while the device is still hot, which poses a risk to the user and the surroundings. In addition to the expense incurred for replacing the brass housing when the cyanoacrylate gets depleted, there is a potential for damage when the brass housing is removed, both to the device and the user.
One recent technique incorporates a butane torch with a metal cartridge that connects directly to a clear plastic fuming housing. This technique uses a metal cartridge encapsulated within which is a marble sized-ball of steel wool positioned between two wire mesh screens. This design allows the user to recharge the steel wool ball, once the cured cyanoacrylate on the substrate is depleted. However, this design has its drawbacks, such as, managing multiple components and additional clean ups, handling of additional cyanoacrylate carried in a small bottle for recharging the steel wool ball, and requiring additional downtime during each recharge, and waiting for the cyanoacrylate to cure.
Therefore, there is a need for an apparatus and method for developing a latent print that reduces the operational cost, provides ease of use, and does not require any significant downtime between applications.